Study of the Low-Lying States of ${\mathrm{Cl}}^{38}$ via the Reaction ${\mathrm{Cl}}^{37}(d,p\gamma ){\mathrm{Cl}}^{38}$

Levels of ${\mathrm{Cl}}^{38}$ below an excitation energy of 2.75 MeV have been studied with the reaction ${\mathrm{Cl}}^{37}(d,p\gamma ){\mathrm{Cl}}^{38}$ at a deuteron bombarding energy of 3.1 MeV. $\gamma$-ray branching ratios and Doppler-shift information were obtained from proton-$\gamma$ coincidence measurements using Ba${\mathrm{Cl}}_2$ targets enriched in ${\mathrm{Cl}}^{37}$. Excitation energies were determined from singles measurements, as well as from the coincidence studies for the 10 levels previously reported in this energy range. The $J^{\pi }=1^{+}$ level at 1942 keV, which is strongly excited in the $\beta$ decay of ${\mathrm{S}}^{38}$ and which was not observed in ${\mathrm{Cl}}^{37}\mathrm{}(d,p)\mathrm{}{\mathrm{Cl}}^{38}$ studies with a magnetic spectrograph, is also weakly populated. Excitation energies (in keV) and mean lives (in psec) for the lowest 10 levels are 671.27 ± 0.16; 755.26 ± 0.11, 0.53 ± 0.18; 1308.87 ± 0.14, ${1.0}_{-0.4\mathrm{}}^{+0.9\mathrm{}}$; 1617.21 ± 0.14, ${2.3}_{-0.9\mathrm{}}^{+2.3\mathrm{}}$; 1692.4 ± 0.2, 1.9 ± 0.7; 1745.8 ± 0.3, ${2.1}_{-0.7\mathrm{}}^{+1.4\mathrm{}}$; 1785.1 ± 0.5, 0.09 ± 0.03; 1941.7 ± 0.2; 1981.11 ± 0.15, 0.43 ± 0.09; and 2743.1 ± 0.4, ≤ 0.03. The multipole strengths of the transitions linking these states with the $2^{-}$ ground state and $5^{-}$ first excited state lead in combination with the $l_n$ transfer values from previous ($d,p$) work to the following spin-parity assignments; $J^{\pi }\mathrm{}\left(755\right)=3^{-}$; $J^{\pi }\mathrm{}\left(1309\right)=4^{-}$; $J^{\pi }\mathrm{}\left(1617\right)=3^{-}$; $J^{\pi }\mathrm{}\left(1692\right)=1^{-}, 2^{-}, or 3^{-}$; $J^{\pi }\mathrm{}\left(1785\right)=2^{+}, 3^{+}, or 4^{+}$; $J^{\pi }\mathrm{}\left(1981\right)=2^{-} or 3^{-}$; and $J^{\pi }\mathrm{}\left(2743\right)=3^{-}$. The experimental results are compared with shell-model calculations and with predictions from the Pandya transformation of the known ${\left(\pi 1d_{\frac{3}{2}}\right)}^{-1\mathrm{}}\left(\nu 1f_{\frac{7}{2}}\right)$ and ${\left(\pi 1d_{\frac{3}{2}}\right)}^{-1\mathrm{}}\left(\nu 2p_{\frac{3}{2}}\right)$ quadruplets in ${\mathrm{K}}^{40}$.